The present invention relates to antennas and, more particularly, to dual band single feed printed dipole antennas.
Printed antenna structures, also referred to as printed circuit board antenna structures, are widely used to provide compact antennas that can be integrated with other microelectronic devices on a substrate. For example, printed antenna structures may be used with cellular telephones, portable computers, electronic games, personal digital assistants (PDAs), or the like.
One common printed antenna is a monopole antenna (the xe2x80x9cMonopolexe2x80x9d). The Monopole is a small, omni-directional antenna that can conveniently fit in most electronic devices. However, conventional Monopole antenna rely on the ground plane for successful operation
Further, data communications devices have been switching to dual band operation. In particular, there is currently a shift in the requirement from the existing single band operation to dual industrial scientific medical (xe2x80x9cISMxe2x80x9d) band operation covering, for example, frequency ranges of 2.4-2.5 to 5.15-5.35 GHz. Traditionally, a xe2x80x9ctrap circuitxe2x80x9d was incorporated in the Dipole design to facilitate dual band operation.
Thus, it would be desirous to develop a dual band Dipole that reduced or eliminated the ground plane and/or trap circuit.
To attain the advantage of and in accordance with the purpose of the present invention, dual band antennas are provided. The dual band antennas include a substrate having a first dipole antenna, have a first ground arm and a first live arm. A second ground arm is connected to the first ground arm, and a second live arm is connected to the first live arm. The second arms form a second dipole antenna.
The present invention also provide a method of marking the dual band antennas. The method includes providing a substrate and selectively metallizing the substrate to form a first half-wave dipole antenna and a second half-wave dipole antenna.
The foregoing and other features, utilities and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention as illustrated in the accompanying drawings.